Cable terminal



April 8, 1930. w. E. scHWAR-MANN EIT Al. 1,753,627

' CABLE wrizmvrIhIALl Filed July 29,

INVENTOR WOLFGANG E. SCHWARZMANN ADOLFH ROSNER ATTORNEY Patented Apr. s,1930 UNITED STATES PATENT oFFicE WOLFGANG E. SCHWARZMANN, OF LONGMEADOW,ANDI'ADOLPH ROSNER, 0F SPRING- FIELD; MASSACHUSETTS, ASSIGNORS, BY MESNEASSIGNMENTS, TO THE ELECTRIC AUTO-LITE COMPANY, A- CORPORATION OF OHIOCABLE TERMINAL Application led July 29, 1921. Serial No. 488,304.

The present invention relates to connectors for electrical cables, suchas those used in ignition systems for internal combustion engines.

I-Ieretofore, the plug member of a plug and socket type of cableconnector, has been made with inwardly projecting pieces that extendedtransversely into the insulating covering of the cable. It wasnecessary, in such member, to manually attach it to the end of the cableby iirst spreading the side portions of the member sufficiently topermit the insertion of the cable and then to forcibly cause the lateralextensions to enter the insulation. When shipping instruments orapparatus using such members, the same, if placed in their respectivesockets, had to be withdrawn from such socketsat the time of attachingthese members to the cable ends and accordingly, could not be attachedto the cable ends while in such sockets.

In accordance with this part of the invention, we form the plug memberwith a plurality ofinwardly projecting and downwardly extending prongswhich` permit the ready insertion ofthe end of the cable in the plugmember, but becomes fixed to the cable when it is moved in the oppositedirection, thus preventing the withdrawal of the cable from the plugmember, the prongs digging into the cable covering for such purpose. Itwill be thus apparent that when the cable is withdrawn from the socketmember,'the plug member will be withdrawn therefrom as a unitary part ofthe cable. In order to give stiEness to the prongs and to reduce theamount of material required for a plug member of a given length, theprongs are preferably located intermediate the ends of the plug member,while the latter may also have at its lower end an inwardly extending`projection adapted ,to enter into the electrically conductive part ofthe cable when the latter is inserted into the plug member. v

Referring more particularly to the accompanying drawing, upon which areshown a few embodiments of the invention, in application, as forexample, to a distributor head and spark plugs of an ignition system forinternal combustion engines:

Fig. 1 is a vertical sectional view of a' distributor head showing theconnectors in connected position; Fig. 2 is a side view in elevation ofthe plug portion of the connector, with the cableend in place therein;Fig. 3 is a longitudinal sectional View of the same taken on line 3 3 ofFig. 5; Fig. 4 is a developed plan view 0f the plug member; Fig. 5 is abottom plan view of the plug member with the cable end in place; Fig. 6is a transverse sectional view taken on line 6 6 of Fig. 3; Fig. 7 is alongitudinal vsectional view of the plug member per se.

' head 1, the lower terminals being formed integral with the socketmembers 6 embedded in the posts or towers 7 from which lead the hightension leads 8 to the respective spark plugs in the engine cylinders.In the center of the head 1 is provided a central tower or post 9 havinga metal insert 10 recessed at its lower end to receive a contact brushmember 11 cooperative with the inner end of the brush 3 in aknownmanner, and provided at its other end with the socket member 12,similar to socket 5, for receiving the end of a high tension lead orcable 13 extending to the secondary winding of an induction coil ormagneto armature; l

The connector comprises, in general, a socket member, such as the member6, and a plug'member 14. The latter is constructed from a sheet metalpunching, shown in developed plan form in Fig. 4 of the drawing. Thispunching or blank comprises, in general, a border portion 15 having aplurality of downwardly extending finger portions 16 and 17 arranged inspaced relation, two of these finger portions being connectedtogether bya transverse connecting member 18, thus rigidly maintaining the relationofthe adjacent or connected fingers 17. Alternating with the fingers 16and 17 are also provided downwardly extending sharpened portions orprongs 19 which are bent inwardly and extend downwardly, as viewed inFigs. 1, 2, 3, 4 and 7 of the drawing, for a purpose hereinafter morefully described. The connecting portion 18 isalso provided with adownwardly extending portion 20 which may be suitably sharpened orpointed and bent to enter into the electrically conductive part of thecable, as will hereinafter more fully appear. It will be observed thatthe portion 20 is located between and adjacent the lingers 17 and issheared or slitted on the lines 21, in order that the member 20 may bereadily shaped into the'form shown in Fig. 3 of the drawing, when thepunching or blank is rolled and shaped for connection with the end ofthe cable. The fingers are also preferably provided with widenedportions 22, such that When bent on the lines 23, as shown in Fig. 4,the end portions 24 will extend inwardly in a transverse fashion at theend ofthe plug member, as is clearly shown in Figs. 2, 3, 5 and 7 of thedrawing, and with the widened portions 22 located near each other, sothat the same may encase or surround the lower end of the cable,particularly the cover thereon, so as to prevent the upward projectionof the frayed ends of the braided threads of the cable sheathing.

The punching or blank is rolled into the form of a cylinder so that theends 25 and 26 thereof will be located adjacent each other and the ends24 bent inwardly as well as the end portion 20, the latter being bentabout the lines 27 and 28, as shown in Fig. 4 of the drawing, thusforming a sort of U-shaped member or hook with the point 29 thereof eX-tending inwardly and upwardly within the interior of the plug member.With the member in the form above described, it will be noted that theprongs 19 extend inwardly and downwardly, so that when the end of thecable is inserted or forced into the plug member, the insulatingcovering of the cable will be permitted to pass by the ends of theprongs 19, but any tendency towithdraw the cable will cause the prongs19 to be forced inwardly into the insulating cover, thus preventing thecable from becoming detached from the plug member, Athe latter thusbecoming fixed to and forming a unitary part of the end of the cable. Itwill be also observed that when the end of the cable is inserted in theplug member, the point 29 of the member 20 '5 is located centrally, sothat it will be forced inwardly into or among the wires of a conductingportion of the cable.l The member 20 lunay be caused to bend as the endof the cable is forced onto or over the point 29, and therefore, for thepurpose of preventing total deformation of the member 20, the endportions 30 of the fingers 17 are so bent and cut that they willover-lap the member 20 at the lower end of the plug shell, as is clearlyshown in Figs. 3 and 5 of the drawing. As

the member 20 is forced downwardly, it will contact with theoven-lapping portions 31 of the portions 30, such over-lapping portionsaccordin 'ly acting as an abutment means for the mem er 20 tofpreventfurther bending thereof, as the end of -the cable is forced into theplug member. A slight backward pull of the cable will cause the prongsto dig in rmlyinto the insulating covering of the cable, and also permitthe member 2O to return to normal shape, such as is shown in Fig. 3 ofthe drawing.

The spring fingers 16 and 17 are also further outwardly bent to formgroove engaging positions 32, which are adapted, when the plug member isinserted in the socket, to snap into or engage in an internal annulargroove 33 formed in the socket member 5. iThe fingers 16 and 17 willradially flex inwardly when the plug member is inserted in the socketmember until the bent portions 32 arrive opposite the groove 33 andresiliently snap thereinto, such bent portions acting to normally holdor maintain the plug member and the attached cable within said socket,yet

permitting the unitary detachment thereof by a strong manual pull of thecable.

It will beobserved that the type of connector above described is notlimited to use in any particular device, such as a distributor head, butmay also be connected to various other devices, such as spark plugs andthe.

like.

The end of the cable is merely cut without further trimming or otherpreparation for connection to the connector. It is merely necessary totransversely cut the cable and then insert the cut. end thereof into theplug member. In the manufacture of electrical equipment, such as thatused in ignition systems, it is customary to ship -the same with theconnector members, particularly the part to be eventually attached tothe cable, tied to the instrument with a piece of wire or cord..

When installing the same, the connector member must then be attached tothe cable. This inconvenience is avoided by the present invention byinsertin the plug member into the sockets of the dlstribu'tor, at thetime of shipment, and when the apparat-us is later installed, it ismerely necessary to cut a cable to suitable length and insert the cutend thereof into the plug member while it is still in its socket. Wardlyinto the plug member, it will pass by the prongs 19 and engage with thepoint 29 so as to establish electrical connection between the latter andthe electrical conductive part of An opposite pull upon the cable As theend of the cable is forced inllli part thereof, the spring fingers 16and 17 readily exing for t at purpose.

We claim: Y 1. A socket fitting plug adapted to be at- 5 tached to theend of an electric cable, comprising a tubular body portion having anopen end adapted t receive the end of the ca le v the sides of said bodyportion being adapted to snugly fit the sides of the cable; a prongintegral with said tubular body portion, forming in part the closure forthe opposite end thereof and adapted to enter the conducting portion ofsaid cable as said cable is inserted into said body portion; means toreinforce said prong against distortion when said cable is so inserted;and means integral with the sides of said body portion adapted to closein upon said cable to prevent the removal of said cable when suchremoval is attempted.

2. An electric cable connector; a plug member adapted to t in o a socketmember the plu member made o sheet material and adapte to be attached tothe end of an electric cable comprising: a tubular portion; a

plurality of finger portions extending therefrom in spaced relation; anextending prong connecting two of said finger portions adapted to bebent forming part of the closure or the end of the cable and arranged toenter the conducting portion of said cable when said cable is inserted;a plurality of/inwardly rojecting prongs alternately extending om saidtubular portion with respect to said ngers and arranged to permit theinsertion of the end of said cable and become fixed thereto.

' 3. An electric cable connector; a plug member adapted to fit into asocket member, the plug member made of sheet material and 4o' adapted tobe attached to the end of an electric cable comprising:atubularvportion; a

pluralit of spaced fingers; a lurality -of cabledholldin prongs betweensai -fingers, the

finger ends eing enlarged-transversely and tapered to a point; a bridgeconnecting two ngers and a piercing (point extending from said bridgeand adapte to enter the conducting portion of the cable when said cableis inserted in said plug. Y

In testimony whereof I aix my siture.

ADOLPH ROS R.

In testimony whereof I affix m signature.

WOLFGANG E. SCHW

